The present work was conducted in a malaria risk area of the Carajás Project (Carajás, PA). Temephos, a widely weed chemical larvicide, as well as a Bacillus thuringiensis H-14 (Bti) based product were evaluated alone or in combination against the malaria vector Anopheles triannulatus. Larval susceptibility was evaluated in terme of LT50and final mortality. The mixture of the two larvicides showed temporal synergism. The susceptibility of Culex rorotaensis larvae and notonectlds was also evaluated to Bti and Temephos respectively. The relevance of the present results is discussed in view of the integrated management of A. triannulatus.